Current research on van der Waals heterostructure-based optoelectronic devices has predominantly focused on two-dimensional (2D) material systems, whereas investigations into the integration of multiferroic thin films with 2D materials within van der Waals heterostructures remain limited. In this study, a hybrid WSe₂/BiFeO₃(BFO)/quasi-two-dimensional electron gas (Q2DEG) heterostructure was successfully fabricated by combining pulsed laser deposition (PLD) with Ar⁺-ion bombardment-assisted (AIBA) techniques. A low-temperature chargeable photoconductivity (CPC) effect was achieved, with the operational retention temperature extended up to 60 K. The results demonstrate that after 30 s of illumination using a 405 nm laser, the peak current of stored photogenerated carriers released upon application of a bias voltage in the dark state reaches 250 μA. Moreover, under a fixed bias voltage of +4 V and at low temperature of 20 K, the device exhibits stable and repeatable switching behavior under varying laser irradiation conditions. Both the photocurrent magnitude and on/off ratio can be synergistically modulated through control of light intensity and wavelength. The CPC effect further demonstrates broad spectral responsivity (405-808 nm), enhanced performance at low temperatures, and robustness against external magnetic field interference. This work not only advances the fundamental understanding of photogenerated carrier separation, storage, and transport mechanisms at multiferroic-2D material interfaces but also establishes a critical materials and device platform for the development of high-performance non-volatile optical memory and neuromorphic computing technologies.